Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
KESTELL
As described in historical dictionaries
Patronymica Britannica (1860)
KESTELL. This family are known to have been resident at Kestell, in the parish of Egloshayle, co. Cornwall, from the time of King John till about the j'ear 1737. C. S. Gilbert's Cornwall.